Translation, cross-cultural adaptation, and reliability of the Understanding COPD questionnaire for use in Brazil

OBJECTIVE: To translate the Understanding COPD (UCOPD) questionnaire into Portuguese, adapt it for use in Brazil, and assess its reliability. METHODS: The UCOPD questionnaire consists of two sections, designated section A and section B. Section A comprises 18 items divided into three domains: “About COPD”, “Managing Symptoms of COPD”, and “Accessing Help and Support”. Section B includes five questions regarding patient satisfaction with the educational component of pulmonary rehabilitation programs. The UCOPD questionnaire was applied twice on the same day by two different raters (with a 10-min interval between applications) and once again 15-20 days later. The Wilcoxon test was used in order to compare the scores among applications. Reliability was assessed by the intraclass correlation coefficient and Bland-Altman plots. RESULTS: The study sample consisted of 50 COPD patients (35 men; mean age, 65.3 ± 7.91 years; mean FEV(1), 36.4 ± 16.2% of the predicted value). Inter-rater intraclass correlation coefficients for section A total scores and domain scores ranged from moderate to high. Section A scores and domain scores had no significant differences regarding test-retest reliability (p < 0.05). The test-retest and inter-rater Cronbach’s alpha coefficients for section A total scores were 0.93 and 0.86, respectively (p < 0.001). There were no floor or ceiling effects. CONCLUSIONS: The Brazilian Portuguese version of the UCOPD questionnaire is reliable.